Strange deflection in ANSYS tensile test of ±45° fiberglass laminate

[Rawllet]

TL;DR

Tensile test, using ACP Pre and Static Structural modules, of a fiber glass laminate with 6 layers orientated +/-45°.

Hello everyone!

I am trying to modelate a tensile test of dumbbell-shaped specimen under ACP PrePost and Static Structural modules. The laminate I am configuring consists of 6 laminas of E FiberGlass orientated +/-45°. For simplicity I am working with 1/4 of the geometry and the boundary conditions are 2 displacements. One that let's movement only in X axis and the other only let's movement in Y and Z axis.

My problem is a strange deflection that is shown in the solutions spot and I do not know what could be the reason of it. I don't know if is because of the boundary conditions or maybe a bad laminate configuration.

I wii be very thankful for any help. I attached a few photos that could help in the understanding of the problem.

Thank you in advance.

 

[FEAnalyst]

Apply symmetry boundary condition to cut edges. Constrain the end of the specimen in all directions and prescribe axial displacement value. To avoid lateral deflection you can restrict deformations to in-plane only using boundary condition applied to the whole surface of the specimen with fixed displacement in Z direction.